Wet-laid nonwoven web from unpulped natural fibers and composite containing same

ABSTRACT

Wet-laid nonwoven webs having mechanical reinforcement properties are provided by employing unpulped vegetable fiber bundles as the predominant fiber component. The unpulped fiber bundles have a modulus of elasticity of about 2-5×10 6  psi and a chopped fiber length of about 25 mm. The fibers are cordage fibers including sisal, abaca, henequen, kenaf and jute. Composites of the unpulped fiber webs with cellulosic and spunbonded sheets find application as thermoformed vehicle interior trim products.

RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.60/036,200, filed January 27, 1997. This is the U.S. national stage ofInternational Application No. PCT/US98/00191 filed Jan. 20, 1998.

FIELD OF THE INVENTION

The present invention relates generally to wet-laid nonwoven webs madefrom unpulped long natural fiber bundles and to hydroentangled compositesheet material containing such nonwoven webs.

BACKGROUND OF THE INVENTION

In conventional wet-laid papermaking operations, pulped fibers aredispersed in an aqueous medium and deposited in sheet form on apaperforming wire or screen. The pulped fibers are the natural singleelementary fiber units obtained from the pulping process. Theseelementary fibers, prior to the pulping process, are bundled togetherand held by several natural binding components such as lignin andhemicellulose. The pulping process removes these binding components,leaving behind mostly the elementary cellulosic fibers. This breakdownof the fiber bundles is desirable since the freed elementary fibers aremore manageable and provide a desired sheet uniformity whilecontributing to the strength and brightness of the resultant sheetmaterial.

In wet-laid nonwoven application, pulped vegetable fibers of increasedlength are employed as compared to the shorter wood pulp fibers. Theselong vegetable fibers impart improved mechanical properties and includeelementary fibers such as sisal, hemp, caroa, flax, jute and abacafibers, as mentioned in Homonoff et al U.S. Pat. No. 5,151,320 andViazmensky et al U.S. Pat. No. 5,009,747. In this connection, the pulpedvegetable fibers typically have a fiber diameter of about 5-30 μm and afiber length of about 10 mm. In publication WO 96,12849, freed or pulpedramie fibers cut to a length of 12 mm have been used in place of 12 mmsynthetic fibers to form absorbent nonwovens when appropriate dispersionagents are employed.

Wet-laid nonwovens of inorganic fibers such as glass, carbon, silicacarbide and others also are known and have been used for compositeapplications where the anisotropic properties of the wet-laid nonwovenare desirable for reinforcement purposes. These inorganic fibersadvantageously impart to the nonwovens their high modulus of elasticity,which result in improved reinforcement at a minimal weight penalty.

Interior headliners for motor vehicles heretofore have consisted ofmoldable multi-layer assemblies comprised of a foam core with layers offiberglass adhered to opposite planar surfaces thereof. A plasticmoisture barrier film such as a polyethylene film is applied to thebackside fiberglass layer (the side closest to the vehicle roof) andpaper fleeces are employed as cover layers over the film to preventsticking during the molding operation. A cloth fabric or equivalentlayer covers the front fiberglass layer closest to the interior of thevehicle. Additionally, as mentioned in the Welch et al U.S. Pat. No.5,437,919, outside layers of woven jute fleece or flax or sisal fleecemay be used. Such headliner materials exhibit not only the necessarythermoforming characteristics, but the fiberglass reinforcing fibersprovide a modulus of elasticity exceeding that of the resin matrix andimpart the requisite stiffness to the resultant product.

For various reasons, the industry seeks to obviate the use of fiberglassin such applications without adversely impacting on the desirablecharacteristics thereof, particularly the thermoforming and modulus orstiffness characteristics.

SUMMARY OF THE INVENTION

It has now been found, in accordance with the present invention, thatdesirable mechanical reinforcement properties can be incorporated intononwoven web materials without using fiberglass or bulky, heavy weightmaterials that have evidenced nonuniform constructions hereinbefore.This is achieved by using wet-laid nonwoven webs made with longvegetable fiber bundles as the predominant fiber component. Suchnonwoven webs may be used individually or as part of compositestructures as the reinforcing or stiffening component of suchcomposites.

It is an advantage of the present invention that the unpulped fiberbundles exhibit the requisite high modulus of elasticity necessary toreplace the inorganic fibers employed heretofore. At the same time, theanisotropic characteristic of the wet-laid nonwoven material ismaintained.

In accordance with the present invention, fiberglass mats can bereplaced entirely by wet-laid sheets composed predominantly of naturallong fibers having an equivalent or greater modulus of elasticity, i.e.,stiffness, of about 2-5×10⁶ pounds per square inch. A nonwoven web ofnatural long fiber bundles may be employed to replace both thefiberglass layer and the barrier film that prevents resin bleed-through.A composite thereof provides multiple layers of thermoplastic fibers,natural reinforcing fibers and woodpulp which, when combined, willwithstand the thermoforming processes required where contouredreinforcement of the finished product is desired, such as in vehicleheadliners or other vehicle interior trim products. The sheet materialof the present invention completely replaces the inorganic reinforcingfibers and employs select unpulped natural long fiber bundles in awater-laid web. The long fiber web material may be used alone or as acomposite to replace the prior three layered structure of fiberglasssubstrate, thermoplastic film and nonwoven backing. The resultantproduct combines lightweight, reduced bulk and high stiffness in moldedform with good moldability and mold release as well as high elongationand barrier properties against resin flow.

Other features and advantages of the present invention will be in partobvious and in part pointed out more in detail hereinafter.

A better understanding of these advantages, features, properties andrelationships of the invention will be obtained from the followingdetailed description which sets forth an illustrative embodiment and isindicative of the way in which the principles of the invention areemployed.

DESCRIPTION OF A PREFERRED EMBODIMENT

The nonwoven fibrous web material formed in accordance with theinvention is made by a wet papermaking process that involves the generalsteps of forming a fluid dispersion of the requisite fibers, depositingthe dispersed fibers on a fiber collecting wire in the form of acontinuous sheet-like web material. The fiber dispersion may incorporateup to 2% by weight, preferably about 1% by weight, of a wet strengthadditive and, following sheet formation, may be used as one component ofa composite to provide the desired synergistic strength and moduluscharacteristics while facilitating use in moldable applications.

The fiber dispersion may be formed in a conventional manner using wateras the dispersant or by employing other suitable liquid dispersingmedia. Preferably, aqueous dispersions are employed in accordance withknown papermaking techniques and, accordingly, a fiber dispersion isformed as a dilute aqueous suspension or furnish of the fibers. Thefiber furnish is then conveyed to the web-forming screen or wire, suchas a Fourdriner wire of a papermaking machine, and the fibers aredeposited on the wire to form a nonwoven fibrous web or sheet. The sheetor web is dried in a conventional manner, but is not treated with anypostformation bonding agent.

The fiber furnish is a blend of natural pulp, man-made fibers and apredominant amount of unpulped natural fiber bundles. The pulp componentof the fiber furnish can be selected from substantially any class ofpulp and blends thereof. Preferably the pulp is characterized by beingentirely natural cellulosic fibers and can include cotton as well aswood fibers, although softwood papermaking pulp, such as spruce,hemlock, cedar and pine are typically employed. Hardwood pulp andnon-wood pulp, such as hemp and sisal may also be used. The natural pulpmay constitute up to about 40 percent by weight of the total fibercontent of the web material.

As mentioned, the nonwoven web material also may contain a significantconcentration of man-made fibers blended with the wood pulp. The typicalman-made fiber is a polyester such as polyethylene terepthalate.However, as will be appreciated, the synthetic fiber component is notlimited to polyesters, but can include other synthetic and man-madefibers that are either non-cellulosic or cellulosic in nature. Forexample, cellulose acetate, viscose rayon, nylon or polyolefin fiberssuch as polypropylene fibers also may be used.

Although substantially all commercial papermaking machines, includingrotary cylinder machines, may be used, it is desirable where very dilutefiber furnishes of long fiber material are employed to use an inclinedfiber-collecting wire, such as that described in U.S. Pat. No. 2,045,095issued to F. H. Osborne on Jun. 23, 1936. The fibers flowing from theheadbox are retained on the wire in a random three-dimensional networkor configuration with slight orientation in the machine direction whilethe aqueous dispersant quickly passes through the wire and is rapidlyand effectively removed.

Synthetic fibers are preferably of a low denier of about 1-6 denier perfilament (dpf) and a length greater than about 4 mm, for example, in therange of 10-25 mm. Generally, the lower denier materials are of slightlyshorter length than the higher denier in view of the tendency of thelower denier fiber to entangle prior to deposition on the web formingscreen. For example, 3 dpf fibers can be used at lengths of about 15 mm,while it is preferred to use a 1.5 dpf fiber at a length of about 10 mmand a 6 dpf fiber at a length of 25 mm. As will be appreciated, stilllonger fibers may be used where desired so long as they can be readilydispersed within the aqueous slurry of the other fibers. Although theamount of synthetic fibers used in the furnish may also vary dependingupon the other components, it is generally preferred that less than 30percent by weight be employed. Typically, the man-made content is atleast 5 percent by weight, with 5-25 percent by weight and preferably5-15 percent by weight being used in most cases.

In addition to the man-made fibers and the conventional papermakingfibers of bleached kraft, the furnish of the present invention includesunpulped natural fibers as the predominant component. As mentioned, somestrength is imparted by the kraft fibers. However, the predominantreinforcement characteristics are achieved in accordance with thepresent invention by including long unpulped vegetable fibers andparticularly the extremely long natural, unpulped fiber bundles ofcordage fibers chopped to a length in the range of 10-50 mm. These verylong natural fiber bundles supplement the strength characteristicsprovided by the bleach kraft and, at the same time, provide a naturaltoughness and burst strength.

The natural long hard cordage fibers are comprised of, but not limitedto, sisal, abaca, henequen, kenaf and jute. These natural fiber bundlesare used in their natural state with varying thickness and a lengthselected so that the bundles can be formed as an individual layer by thewet-laid process. The fibers are kept in their bundle configuration andcontain the naturally occurring lignin, hemicellulose and otheringredients. As indicated, the bundles are not pulped. A comparison ofthe fiber diameters of pulped elemental fibers and the unpulped fiberbundles is set forth in Table I. The long natural fiber bundlestypically comprise at least 30% by weight of the fiber content of thenonwoven material and are the predominant fiber component. The preferredrange is 55-85% by weight, as contrasted with the range for pulp of5-40%, with good results being obtained in the range of 60-75% byweight.

TABLE I Unpulped Unpulped Pulped Fiber Diameter Fiber Denier FiberDiameter Fiber (μm) (g/9000 m) (μm) Sisal 137 to 193 206 to 406  7 to 47Abaca 113 to 158 139 to 273 10 to 32 Henequen 182 to 188 362 to 383 —Kenaf 68 50 10 to 32 Jute 37 to 50 15 to 27  5 to 25

Although fiber bundle lengths up to 100 mm or more may be employed, themore typical longest fiber bundles utilized are about 50 mm or less inlength. Products made from fibers having a length range of about 10-35mm are preferable with commercial products frequently having a fiberbundle length of about 20-30 mm. It is of course appreciated that thefiber bundles can readily be chopped to any desired length and are notchemically pulped but used in their natural state.

As mentioned, the remaining fiber components in the long fiber webconsist of woodpulp, synthetic fibers or mixtures thereof. These assistin the processing of the wet-laid web material and typically are presentin lesser amounts. The preferred amount is about 10-20% each. When bothpulp and synthetic fibers are present, they are in a ratio ranging from1:5 to 5:1, with the preferred ratio being in the range of about 1:2.5to 2.5:1. The synthetic fibers may be of one material, mixtures ofsynthetics, bicomponent fibers or binder fibers. Materials such aspolyesters or polyolefins are typical.

The properties of the nonwoven are enhanced for use by the addition of asuitable binder or wet-strength agent. Suitable binders can include boththe chemical binders such as acrylics, polyvinyl alcohols, vinylacetates, styrene derivatives such as styrene butadiene rubbers,polyesters, and other traditional chemical binder families; as well assynthetic binder fibers. Synthetic binder fibers commonly used are thepolyvinyl alcohols, and the many bicomponent temperature sensitivefibers such as polyolefin and polyesters. A suitable binder content canbe in the range of 2 to 30 weight percent of final product, with thelower end of that range being preferred, such as about 3-10% with about5% being most preferred. Binder addition is accomplished by the commonchemical methods, wet-end additions, and thermal conditioning. In placeof chemical binders, the webs may be hydroentangled.

The basis weight of the long fiber nonwoven web material may vary fromabout 50-80 g/m² to about 200 g/m² depending on the desired end use. Thepreferred material has a basis weight in excess of 100 g/m² andtypically falls in the range of about 105-135 g/m² and more preferablyabout 120-130 g/m².

The composite multilayer materials made from the long natural fiberbundle webs are formed by combining a layer of such a nonwoven with astretchable first layer of high content thermoplastics, such as fiberswith a low melting point temperature, and a cover layer of high contentwood pulp or other natural or synthetic heat resistant fibers. Thecomposite can be formed by taking three individual and distinct layers,or a number of other layered combinations having the above-statedproperties, and hydroentangling them together to form a single finishedcomposite product. Other methods of combining the various layersinclude, but are not limited to needle punching, thermal point bonding,adhesive lamination, and multi-phase wet-laid forming.

Typically, the hydroentangling operation is carried out in the mannerset forth in Homonoff et al U.S. Pat. No. 5,515,320 issued Sep. 29,1992, the disclosure of which is incorporated herein by reference. Whilethat patent relates to a fiber web having a significantly higher manmadefiber content, preferably within the range of 40-90 percent man-madefiber, the hydroentangling operation described therein can efficaciouslybe employed with the web material of the present invention. Thehydroentanglement treatment entangles together the fibers forming theweb in such a manner as to provide a total energy input that preferablyis less than about 0.4 horsepower-hours per pound of web. The totalenergy required to treat the web can range from as low as 0.01 andtypically falls within the range of 0.1-0.25 horse-power-hours per poundof web.

The preferred material for the high thermoplastic content first layer ofthe composite can be spunbonded sheets of all kinds, spunlaced material,or others, including meshes, all having elongation properties preferablyof 15% or more in both planar directions. The preferred thermoplasticsare low melting point polyolefins, such as polyethylene orpolypropylene, but can include other materials depending on thethermoforming temperature requirements of the composite. Commerciallyavailable spunbond layers may be employed. These exhibit a basis weightof about 10-50 g/m² with 20 g/m² material being preferred. During thethermoforming process, the thermoplastic content of this layer will meltand behave as a resin matrix for the reinforcing natural fibers, and asa gluing agent to aid in adhesion to other molded part components of aheadliner assembly.

A cover layer is placed on the opposite side of the long fiber web fromthe spunbond layer and is typically a high wood pulp content substratesuch as a paper or nonwoven. Other fibers can be used in the cover layerif they are heat resistant during thermoforming conditions and areequally able to provide good mold release and resin flow barriercharacteristics. Candidate fibers include, but are not limited topolyaramids and their pulps. The preferred method for fabricating thislayer is the wet-laid process due to its formation qualities and theability to control porosity.

Once the wet-laid fiber bundle sheet has been formed on the papermachine, it may be layered with the spunbond substrates as the bottomsheet and the high wood pulp nonwoven as the top or cover sheet and thecomposite hydroentangled.

A following sandwich or composite configuration of a natural fiberbundle layer between the two confining layers readily may be used forreplacing the current glass/film/nonwoven laminates.

1. Spunbond (or spunlace) of low melting point thermoplastic e.g.,polypropylene or polyethylene

2. Chopped natural fiber bundles (with or without other fibers)

3. Wet-laid pulp: cellulose/PET, etc.

The central layer is of substantially greater stiffness, bulk and weightthan the enclosing covering layers. The spunbonded layer provideselongation and gluing to other layers in the composite while thewet-laid cellulose covering provides barrier properties and good moldrelease characteristics.

Having generally described the invention, the following examples areincluded for purposes of illustration so that the invention may be morereadily understood and are in no way intended to limit the scope of theinvention unless otherwise specifically indicated. All amounts are on aweight basis unless otherwise specified.

EXAMPLE 1

A series of hand sheets was made using a Williams-type laboratory sheetmold. The fiber furnish consisted of 80% unpulped long vegetable fibers,15% softwood pulp and 5% polyvinyl alcohol fibers having a length of 4mm and a denier of 1 dpf (sold by Kuraray Co., Ltd. under the trade nameVPB 105-2). The long unpulped vegetable fibers used were Ecuadorianabaca, East Africa sisal, Chinese kenaf and Belgian flax. The lengths ofthe chopped fiber bundles are set forth in Table II. Ten (10) handsheets of each vegetable fiber type were made at a final sheet basisweight of 100 g/m². These hand sheets were in turn used asreinforcements on each side of a semi-rigid polyurethane foam core,commercially available from Foamex International, Inc., having a size of250 mm×250 mm×6.5 mm and a foam density of 30.4 Kg/m³. The foam handsheet sandwich construction was glued employing a polyurethane adhesive,Reichold # 2U010, and catalyzed on a 10:1 ratio using Reichold #22014. Atarget of 40 g/m² of adhesive was applied on each side of the foam withthe glue being applied with a hand roller and the catalyst with a spraybottle. As an outer layer to the reinforcing hand sheets, a mold releasepaper of cellulose fibers having a basis weight of 22 g/m² was used. Inall sandwich constructions, the release paper on each side became partof the final composite.

The sandwich composites were heat pressed at 290° F. for 50 seconds to afinal thickness of 5 mm using a laboratory platen press, Model #Q-230Cmade by Pasadena Hydraulics, Inc. As a control comparison foam coresandwich samples were also produced with the reinforcement sheet being afiberglass mat having a basis weight of 88 g/m².

The finished foam core sandwich samples were cut to provide ten (10)test specimens per fiber type. These specimens were tested for compositestiffness following the standard procedure per ASTM D790-96a. This is athree point flexural test that measures the force to produce a specimendeflection of 0.25 inches at its mid-span. The span between the samplesupports was held constant as was the span to depth ratio.

Table II presents a summary of the measured test properties for the foamcore sandwiches. The data clearly shows that unpulped vegetable fibersare a suitable substitute for glass fibers in these types of foam coresandwich composite structures, typically used in automotive headliners.As a minimum requirement a deflection force of 10N (2.25 lb_(f)) istypically specified for automotive headliners. All the compositesincorporating the natural fiber bundle wet-laid nonwoven hand sheetsexceed that minimum. Other applications for the long natural fiberwet-laid nonwoven can be envisioned in areas where fiberglassreinforcements are used, such as in construction applications, wallcovering, plastic moldings, and others.

TABLE II Modulus Avg. of Fiber Length Adhesive Avg. DeflectionElasticity Fiber Type (mm) Weight (g) Force (lb_(f)) (psi) Sisal 22 6.294.51 ± 0.80 42,508 Abaca 25 6.58 4.26 ± 0.56 40,091 Kenaf 25 7.35 3.36 ±1.18 31,595 Flax 13 7.26 3.11 ± 0.64 29,305 Glass 51 7.39 2.61 ± 0.5024,595

EXAMPLE 2

This example shows that chemical binders can be used to bond the longnatural fiber wet-laid nonwoven, instead of the binder fibers of Example1.

A wet-laid nonwoven was formed with a fiber furnish consisting of 65%unpulped sisal fiber chopped to a length of 22 mm, 10% 18 mm×1.5 denierpolyester fiber, and 25% flash dried wood pulp. The web was formed on aninclined wire papermaking machine resulting in a material having a basisweight of 123 g/m². The formed nonwoven web was transferred from theforming wire, dried and a liquid binder was applied by a two-sided spraystation. The binder used was ethylene vinyl acetate (EVA), (Vinnapas426, available from Wacker-Chemie GmbH). The spray solution was at 6%solids of EVA, and binder pick-up by the web was 6.5 g/m², for a finalnonwoven basis weight of 130 g/m². The properties of the nonwoven areset forth in Table III.

EXAMPLE 3

This example shows that by employing the same forming and bondingconditions as in the above example, other fiber furnish compositions canbe used to impart different properties to the wet-laid nonwoven.

In this example, the fiber composition employed was 70% of 22 mm choppedunpulped sisal fiber, 10% of polyethylene/polypropylene 5 mm×2.2 denierfiber, (type Herculon T-410 from FiberVisions) and 20% of flash driedwood pulp. The same EVA binder as Example 2 was used at the same weightlevel to achieve a final web basis weight of 130 g/m². Table IIIprovides the physical properties of this web for comparison with the webfrom Example 2.

TABLE III Example 2 Example 3 Basis weight (g/m²) 128.9 131.7 MD Tensile(N/m) 1436 942 CD Tensile (N/m) 709 491 Thickness (μm) 1382 1405 Density(kg/m³) 93 94 MD Elongation (%) 4.5 2.9 CD Elongation (%) 7.7 4.7

EXAMPLE 4

Various examples of hydroentangled composites incorporating the longnatural fiber wet-laid nonwoven as the middle layer of a three layercomposite are listed below. The composites were hydroentangled at a linespeed of about 35 ft./min. Four entangling units, each having 51holes/in. and 92 μm-hole size direct water jets against the topcellulose layer to achieve the desired hydroentangled effect. Thecellulose fibers upon impact by the water jets are pushed into themiddle and bottom layers, providing satisfactory mechanical bonding.

Sample Composition of Layers A Top: 31 g/m²: 65% cellulose pulp, 35%18-mm PET (no binder) Middle: 80 g/m²: 40% unpulped sisal, 20% unpulpedabaca, 10% softwood, 10% PE pulp, 20% 20-mm PET (no binder) Bottom: 20g/m²: 18% point-bonded polypropylene spunbond B Top: 31 g/m²: 65%cellulose pulp, 35% 18-mm PET (no binder) Middle: 80 g/m²: 40% unpulpedsisal, 20% unpulped abaca, 10% softwood, 10% PE pulp, 20% 20-mm PET (nobinder) Bottom: 10 g/m²: calendered polypropylene spunbond C Top: 40g/m²: 65% cellulose pulp, 35% 18-mm PET (no binder) Middle: 60 g/m²: 60%unpulped sisal, 10% softwood, 10% PE pulp, 20% 20-mm PET (no binder)Bottom: 20 g/m²: 18% point-bonded polypropylene spunbond D Top: 31 g/m²:65% cellulose pulp, 35% 18-mm PET (no binder) Middle: 60 g/m²: 60%unpulped sisal, 20% softwood, 20% 20- mm PET (no binder) Bottom: 30g/m²: calendered polyethylene spunbond

The properties of the resultant composites are listed in Table IV.

TABLE IV Sample A B C D Basis Weight (g/m²) 133 108 127 114 Dry MDTensile (g/25 mm) 2683 1755 3318 1374 Dry CD Tensile (g/25 mm) 1290 556692 608 Dry MD Elongation (%) 22.3 18.6 28.6 10 Dry CD Elongation (%)38.6 39.1 11.4 17.6 Dry MD Toughness (G cm/cm²) 326 174 343 65 Dry CDToughness (g cm/cm²) 186 94 35 36 Mullen Burst g/m²) 3780 1634 2669 1200

EXAMPLE 5

Long natural fiber bundle wet-laid webs were prepared on pilot andcommercial equipment and were tested as substitutes for glass fiber matsin a vehicle headliner structures. The natural fiber mats were employedin various combinations as either single ply resin bonded structures oras multi-layer composites. Four such samples are set forth below assamples A-D and the physical data thereon is tabulated in Table V.

Sample A—Composite-Hydroentangled

Top: 35 g/m² cellulose/PET

Middle: 110 g/m² unpulped sisal/polypropylene/cellulose

Bottom: 20 g/m² polypropylene

Sample B—Composite:

Top: 35 g/m² cellulose/PET

Middle: 22 g/m² polyethylene film

Bottom: 130 g/m² unpulped sisal/PET/cellulose

Sample C—Single Ply:

125 g/m² unpulped sisal/PET/cellulose, 15%-20% EVA Binder

Sample D—Single Ply:

135 g/m² unpulped sisal/PET/cellulose, 4% Binder Fiber

TABLE V Sample A B C D Basis Weight (g/m²) 168 185 127 135 Dry MDTensile (g/25 mm) 3120 13200 6590 1135 Dry CD Tensile (g/25 mm) 14604950 2870 495 Grain (CD/MD) 0.47 0.375 0.436 0.436 Dry MD Elongation (%)20.1 17.2 12.8 2.2 Dry CD Elongation (%) 39.1 18.8 23.6 7.9 Mullen Burst(g/m²) 3100 — 4060 790 Sisal Content (g/m²) ˜65 ˜65 ˜65 ˜93

The samples were used in the front side (adjacent the face fabric)/backside combinations indicated in Table VI and were molded into a vehicleheadliner configuration. The mold temperature employed was 143° C. andthe dwell time was 50 sec. All samples exhibited good mold release,satisfactory bleed through protection and adequate stiffness and allpassed a humidity test at a relative humidity of 95% at 38° C. for 100hours.

TABLE VII Headliner Trial 1 2 3 4 5 6 Front Side Layer Nonwoven C C C DD D Sample Back Side Layer Nonwoven C B A B D A Sample Total SisalContent, (g/m²) 130 130 130 158 186 158 (Front and Back) Total NonwovenWeight, 254 312 295 320 270 303 (g/m²) (Front and Back) TransverseStrength, MD (N) 18.4 19.3 13.9 18.5 19.8 14.5 Transverse Strength, CD(N) 8.8 9.2 10.1 9.2 13.6 11.0 Geometric Mean Transverse 12.7 13.3 11.813.0 16.4 12.6 Strength

The elongation properties of Sample A permit its use for deep drawmolding configurations, primarily due to its hydroentangled structure.On the front side, the high binder content of Sample C caused it towrinkle and the wrinkles tended to “read through” the fabric. Therefore,Trial 6 is preferred for deep draw molds.

As will be apparent to persons skilled in the art, various modificationsand adaptations of the structure above described will become readilyapparent without departure from the spirit and scope of the invention,the scope of which is defined in the appended claims.

We claim:
 1. A wet-laid nonwoven web material comprising a predominantamount of unpulped long natural fiber bundles and a pulp fibercomponent, wherein the unpulped tong natural fiber bundles are comprisedof a plurality of elementary fibers substantially joined by naturalbinding agents.
 2. The nonwoven web material of claim 1 wherein thenatural fiber bundles are cordage fibers.
 3. The nonwoven web materialof claim 1 wherein the natural fiber bundles are selected from sisal,abaca, henequen, kenaf and jute.
 4. The nonwoven web material of claim 1wherein the long natural fiber bundles have a chopped fiber length inthe range of 10-50 mm.
 5. The nonwoven web material of claim 1 whereinthe web has a basis weight of about 60 g/m² to about 160 g/m².
 6. Thenonwoven web material of claim 1 comprising a synthetic fiber component.7. The nonwoven web material of claim 6 wherein the synthetic fibercomponent is selected from cellulose acetate, viscose rayon, nylon andpolyolefin fibers.
 8. The nonwoven web material of claim 1 wherein theweb has a basis weight up to about 200 g/m².
 9. The nonwoven webmaterial of claim 1 wherein the web has a basis weight of at least about100 g/m².
 10. The nonwoven web material of claim 1 wherein the unpulpedfibers have a modulus of elasticity in the range of about 2-5×10⁶ psi.11. A composite multi layer sheet material comprising a wet-laidnonwoven fibrous web material wherein the dominant fiber component isunpulped long natural fiber bundles and a pulp web secured thereto. 12.The composite sheet material of claim 11 wherein the layers are securedby hydroentanglement.
 13. The composite sheet material of claim 11wherein the layers are secured by chemical bonding.
 14. The compositesheet material of claim 11 including a spunbonded web on the oppositeside of the nonwoven from the pulp web.
 15. The composite sheet materialof claim 11 wherein the composite is thermoformable under pressure. 16.The composite sheet material of claim 11 including a foam layer with thenonwoven web material of claim 5 secured to opposite sides thereof. 17.The composite sheet material of claim 11 having an average deflectionforce of at least 2.25 lb_(f).